


Rumor Has It

by ichikonohakko



Series: Behind Closed Doors of Class E [3]
Category: Assassination Classroom
Genre: F/M, Gen, M/M, Others will come and go but this fic focuses on Nagisa's life as the new Koro-sensei of 3-5
Language: English
Status: In-Progress
Published: 2016-03-18
Updated: 2016-03-28
Packaged: 2018-05-27 11:56:53
Rating: General Audiences
Warnings: No Archive Warnings Apply
Chapters: 6
Words: 4,543
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/6283540
Author URL: https://archiveofourown.org/users/ichikonohakko/pseuds/ichikonohakko
Summary: <blockquote class="userstuff">
              <p>Rumor has it that Shiota-sensei used to be an assassin, and Principal Asano asked for him specifically to intern here in Paradise High right after he finished university.</p><p>(Or how the delinquent students of Class 3-5 try desperately to kill Shiota-sensei only to find the other smiling as if fond towards them.)</p>
            </blockquote>





	1. Adachi Hiroshi

**Author's Note:**

> So, this will be a drabble series that is set in one universe, not set in linear line, all of it concerning class 3-5 of Paradise High. There are currently 30 students in 'the 5 as in Delinquent Class' of Paradise High, 10 of them are currently suspended after a huge fight in schoolyard. There are 20 boys and 10 girls in this class, all of them are problem children on their own.
> 
> Currently I'm envisioning 30 chapters for each students, I hope I can get it all done.

The class went deadly silent as the short wimpy teacher held Miura by the neck and practically smiled at them, telling them that if they wanted to kill him they had until graduation. Blue hair, blue eyes, polite smile as he asked them to sit down and begin roll call.

Miura was, of course, the last one to sit down. Still shell-shocked and absently rubbing the spot on his neck where the shorty had touched him on. Adachi went to his seat, feeling a teensy bit nostalgic since he hasn't sat on his seat for quite some time now. Roll calls are so rare these days as Ayukawa would just check everyone in and so they never had to take a roll call. No teacher dared to question their actions, save for the new principal, and now this shorty who smiled at them fondly.

"Seat Number 1, Adachi Hiroshi." The shorty called, and he cocked his head just a little to show reaction. Other teachers would have ask once more because of the lack of reaction, but the shorty stared right at him and smiled. "If you don't answer, I can't hear you, can I? But yep, you're here." Adachi nearly narrowed his eyes, but showed absolutely no reaction.

Imai poked his shoulder as he handed a note with scribbles of  _'Dude, this shorty's weird'_ (all in hiragana, Imai couldn't write kanji for shit) and Adachi just nodded. The rest of the class were the same, even the girls seemed more interested in the class' events more than the occassional snaps of picture and returning to their usual fiddling on their handphone. There was a new sensation of curiosity lingering in the air as all attention are focused on the short teacher who didn't look like he was in trouble like others usually would. Teachers for Class 3-5 are usually divided into two categories: the helpless idiots who would find themselves resigning after a month and the 'i'm-not-paid-enough-for-this-shit' types who'd let them have self-studies for the whole semester. Adachi licked his lips, trying to sort the new teach--Shiota Nagisa into one of the two, but so far he hasn't been helpless and he had cared enough to make a roll call.

After the roll call has finished, the shorty closed the book and smiled to them all as he opened his arms with a smile. "I don't have super speed or infinite knowledge, but I do try my best to learn. I hope we can learn together until graduation. As I said before, if you want to kill me I'd be welcoming you with open arms. You have until graduation to try!" 

There were shouting, and Adachi honestly can't stop himself. He'd fucking kill this guy, only to see how he'd react other than that fucking goofy smile of his.


	2. Arata Tomoki

Arata Tomoki honestly couldn’t believe his eyes.

He didn’t come to school for one measly day and now they have a roll call during homeroom instead of the usual arm-wrestling tournament? What the hell?

Their newest playtoy Karura-chan was nowhere to be seen, replaced with a blue haired young boy who didn’t look like he could be taller than 160cm. Is this kid a teacher? _Their_ teacher?

Arata looked over towards Urara—oh, he meant Sakurakouji. The fucking bitch didn’t wake him up to go to school today too, who shrugged in her seat.

“And you are…?” The teach approached him a smile on his face and the roll call book on his hands. Arata, too shocked to say anything, stuttered his own name.

“So you are Arata-kun? I must say that your English test are impressive, even more impressive than the—“ a rubber eraser flew over from the back of the class, aiming straight for the teacher’s temple, but the short kid just deflected it without any second thought with the roll call book. “—others from Class 1 until Class 4. I will tolerate your lateness today because you didn’t come yesterday, but you will have to do penalty next time, okay?”

Arata honestly didn’t know what to say, but he narrowed his eyes and found himself asking the question everyone else must have been thinking. “Who do you think you are…? Spouting orders like that…” It didn’t even sound malicious. This teach honestly didn’t know jack shit about how things are run here in Class 5 as in Delinquent Class.

The boys are _screaming_ , and it puzzled Arata to see that Kazuki didn’t join in. Did he lose the crown when he was absent?

“Yeah!” Adachi’s voice thundered. “You can’t come here spouting orders like that! You may have silenced Miura, but you’re just some brat out here.” Arata’s eyes narrowed at that. He grabbed the teacher’s collar. “Did you do something to Kazuki, you punk…” He whispered so low that it went nearly inaudible. But he was angry. Nobody hurts Kazuki or Urara, especially when he’s absent.

The teacher looked at him; first with a blank expression and then with a somewhat sad, but a definite proud smile. He dropped the roll call book and pat Arata on his head. “You must really want to protect them. Good job!” The teach praised. But then he flicked away Arata’s hand with his left hand and went behind him almost as fast as lightning, Arata almost froze up in fear, but the teach only pushed his back a little. “Please sit down, the first period is English. I have a feeling that you will excel in this class, Arata-kun.”

The teach took the fallen book and went over to the teacher’s desk as the class silenced behind him. He could hear Imai’s (loud as usual) whisper of “Not again…”

Arata went over to his seat next to Adachi, cursing his seat number that put him so far from both Kazuki and Urara. But he guessed that Adachi and Arisugawa aren’t so bad. Adachi looked at the teacher, mouth hanging open in awe as he absently took out his English notes. Arisugawa didn’t even look up from his gaming console.

He _really_ need to ask just what on earth happened yesterday.

**Notes for the Chapter:**

> Seat Number 2 Arata Tomoki are childhood friends with Seat Number 14 Miura Kazuki and Seat Number 23 Sakurakouji Urara :)


	3. Arisugawa Banri

“Please, Nagisa,”

Banri looked up from the PSP when he heard Principal Asano’s sighing voice. Poor guy has only been a principal for 6 months and already he had to deal with the nightmare that is Paradise High. “Asano-kun, I only just graduate, I can’t be a full-fledged teacher without experience as an assistant teacher…”

“You are the literally the only person in this world who would and _could_ help those children. Even Kaede recommends you. Please, Nagisa…” Because he couldn’t see the principal’s face, Banri was half-sure that the man’s could be doing a dogeza. He couldn’t care less, obviously, but it seemed interesting. So he leaned on the door, trying to listen in more closely.

‘Nagisa’ is silent, and Banri couldn’t even hear anything that indicates this man’s presence. Principal Asano still has the small sound of his shifting on the chair, or the sound of how his feet are tapping impatiently into the ground. But this ‘Nagisa’ exudes nothing.

“Did Kayano-chan say anything about me?” The man breathed, sounding as polite but there was a lingering attachment in his voice. “She recommended your services regarding this issue of mine. And I still have to thank you for attending our wedding, we didn’t get to talk much during the reception.” The room fell into silence.

Then Principal Asano shifted, the creaking of his seat gave away that it was a huge gesture, Banri stilled. “Class 3-5 is a structure made by the previous generations of this school’s principal to round up all the problem children in Paradise High in one place, doesn’t this sound familiar?” His voice was slithery, like a whisper and Banri had to strain his ears. “This is possibly the only place where you can find another type of assassination classroom, just like the one you came from…” Banri’s eyes widened and he took a few steps away from the door. Assassination classroom…?

‘Nagisa’ answered, his voice cold and deadly calm. “No place will ever be a classroom like that one, Gakushuu-kun.” Banri shuddered at his tone. “I’m the one who killed Sensei, I understand that the best.” ‘Nagisa’ added as an afterthought, and Banri found himself feeling an emotion he never thought he had: fear.

“Please give this some thought, Nagisa. I will write a letter to your university, maybe they can persuade you better than I can. Same thing with Akabane, too.” His voice had a sound of dismissal. Banri made adjustments, making it as if he was just passing by. He could hear the polite ‘Thank you, Asano-kun’ before ‘Nagisa’ opened the door.

Eyes glued to his PSP’s screen, Banri couldn’t see the man’s face, only flash of blue hair and pale skin as he passed by. But the man had a cold smile on his face, one that he would wear whenever he had bought a new challenging game.

* * *

 

“He needs to be taught a lesson.” Imai prattled from the seat diagonal to his own. How Adachi, Arata, and Imamura could stand him, Banri don’t even know. “I dunno, man.” Adachi sighed. “He got Miura, and Miura’s practically the best here. Who’s to say that he couldn’t get any of us? What do you think, Arata?”

“I’m more interested in finding out just how on earth he got the skills to beat Kazuki.” Arata wondered. “The guy grew up in a fucking Dojo! Ura—Sakurakouji’s place is insane, but he still managed to get him?” Banri chuckled to himself. “No wonder, since he grew up in a place called assassination classroom…”

But the guys heard him just fine.

“What?”

“You heard me right, he used to be an assassin.” The reaction was exactly like Banri had suspected it would be. Adachi, the ever Hitman series lover looked awed while Imai looked like he was going to hit Banri on his face. Arata had a blank look on his face. “Just how the hell did you—“

“Okay guys, please sit down. We’ll begin homeroom now!” Shiota-sensei appeared, with the same default smile and positive outlook on their class. Adachi, Arata, and Imai grudgingly went back to their places.

Behind him, Irie chuckled lowly to himself. “Assassin? Let’s see that for ourselves, shall we?’ And then he threw a knife from underneath his desk, a deranged smile on his face as he did that. Banri was used to Irie’s random episodes by now and he ducked.

Shiota-sensei took a few seconds before noticing that a knife is flying towards him, but the teacher sidestepped it almost easily and gracefully. “Irie-kun, this is a dangerous item you dropped there.” He didn’t even break his smile. But he went over to Irie’s desk just behind him and Banri felt the temperature dropped a few degrees. “I believe I did say that you are free to try to kill me until graduation, but having a real metal knife without knowing how to use it correctly is dangerous…” He twirled the knife around his fingers and gave the hilt back to Irie. “Do consult me after hours if you want some private lessons, okay?”

Taking a deep breath, Banri calmed himself for the roll call. And when the kind voice rings out “Seat Number 3, Arisugawa Banri-kun.” came, Banri, earning gasp of surprises from his classmates, raised his hand.

He couldn’t wait until Mei return from suspension. He had a cool story to tell, after all.

**Notes for the Chapter:**

> When I read the last chapter, I never once think that Kayano and Nagisa ended up together. Like, she just said that she's like an afterthought to Nagisa. So I made her marry Asano so my headcanon KaruNagi may exist in this universe.
> 
> Seat Number 3 Arisugawa Banri's only friend in school is Seat Number 20 Ozaki Mei, they bonded through gaming (and because Mei has a personality issue)


	4. Banjou Ataru

“Oh, welcome home Rui.”

“You’re going out?”

Ataru nodded, restraining the urge to bring out an old joke about how Rui looked pissed. Suspension worked like a holiday for both Banjou siblings, and Ataru knew that even this second Rui is pissed that Ataru was suspended. Serves him right, Ataru had told him that the schoolyard skirmish would be fun but Rui had been stubborn and insisted that he wanted to go the arcade instead.

There were 20 of them back in the yard a few days ago, Ozaki was being an idiot as usual and had decided that a good old brawl would be nice to let out some stress. And of course, Ui would never miss any occasion he could use to piss Ozaki off. And the two had brawled in the yard just below Principal Asano’s office and things just happened. Even some girls are involved in the fight and it was probably the best yard fight Ataru ever done. Rui was still pissed that he went to the arcade with Imai.

The week is almost over, and he’d start school on Monday like usual. Rui had warned about new teach that could sidestep Irie’s knife (and he heard that the teach didn’t even give Irie detention for bringing knife into class, holy fuck) but quite honestly, Ataru shrugged him off. He didn’t really care.

“Arcade? You meeting up with anyone?” Ataru shook his head. “Nah, I’m off to do you-know-what.” Which meant Dance Dance Revolution alone by the corner of the arcade. It was honestly a guilty pleasure for Ataru and he thanked God that Rui didn’t have his prankster gene. His twin brother rolled his eyes and sigh. “Have fun bro. We have homework due tomorrow.”

“Holy shit? Since when do you care about that?”

“I wanna attend the private knife lessons, Shiota-sensei said I gotta hand over tomorrow’s homework.” Rui didn’t give him any second before slamming the front door in his face. Ataru burst into a laughter, genuinely laughing his brother for even thinking to submit homework.

After a few minutes of good laughter, Ataru took a deep breath and shouted ‘I’m leaving!’ towards his brother, Rui didn’t shout back.

Oh well, time for some DDR.

* * *

 

The arcade is honest-to-god crowded, no idea why. There are girls (weird) and some school boys crowding around the door, not actually going inside the arcade. Ataru glared at them and they all made ways for him. What the fuck is going on here? Why is it so crowded in front?

His feet automatically went over to his usual DDR machine, the one in the very back just near the toilets, only to spot a woman with nurse outfit dancing on his machine.

The fuck?

There are three other men watching her play while talking amicably towards each other. Ataru narrowed his eyes and went over to the nearest Tekken machine, silently and grudgingly waiting for the lady to stop. Man, she’s a fully grown adult! Why the hell is she playing DDR in the weekdays?

But Ataru lingered, watching as the lady hit 1000 combos, and when the song is over the machine blared a new record.

“Wow, Kanzaki-san!!” One of the men, the one wearing baseball jacket beamed excitedly as the woman smiled at him. “It’s just a game, Tomohito-kun.” She smiled gracefully and they kissed, there and then. Ataru had the decency to look away. “And you are still calling me with my family name? We are getting married in 6 months.” She giggled, and the baseball player—FUCK! THAT’S SUGINO TOMOHITO! RUI WILL BE FLIPPING SHIT IF HE HAD COME HERE!

With his mouth still open, suddenly there was a well-dressed redheaded man who sat in front of his machine. “Would you play co-op with me?” He said, voice hinting utter mischief. Ataru, still shocked from seeing Rui’s idol in person, nodded dumbly.

And that was thirty minutes ago, not once did he win against the red-haired stranger, who would laugh whenever he lost. Feeling absolutely pissed, Ataru nearly stand just to kick the machine, but a pair of pale delicate hands encircled his own and Ataru froze.

He didn’t even sense anything?! How on earth did he…?

“Karma-kun always uses the same strategy over and over again, just with different characters. You’ll get him if you do this.” And the stranger practically played his hands until they reached victory.

The red-haired stranger laughed. “Oh come on, Nagisa. I was having so much fun.” Ataru turned, seeing a blue-haired man with bluer irises sighing exasperatedly. “Don’t goad my students into doing violence in public, Karma-kun. This isn’t high school anymore.” My students? _What?!_

“Banjou Ataru-kun, yes? I know you’d be here…” A polite smile. What on the flying fuck…? “Rui-kun did say that you often frequent here on your suspension. I shall be expecting you Monday at school, okay?” His smile was cold and yet warm at the same time. The bastard redhead licked his lips. “You know that you look sexy when you do that, Nagisa.”

“Oh stop that, Karma-kun. Come on, Kanzaki-san and Sugino-kun have been kind enough to have a small reunion with us.” And they walked over to Sugino Tomohito and his lover, nearly without a sound.

And Ataru’s instinct screamed:

_These people are not fucking normal._

* * *

 

On Monday, Ataru surprised Rui by raising his hand in class and asking to join the private knife lessons. How could he not? After he saw Sugino Tomohito, his nurse lover, the redheaded bastard and _this_ Sensei sparring with what seemed to be a plastic knife in an abandoned alleyway?

**Notes for the Chapter:**

> Seat Number 4 Banjou Ataru and Seat Number 5 Banjou Rui are fraternal twins


	5. Banjou Rui

**Notes for the Chapter:**

> Sorry for not updating for a few days, I've been having an on-and-off fever bcs of my wisdom tooth growing. Please enjoy this chapter :)

Banjou Rui has always lived with the fact that his brother is a delinquent. And since Rui never really care to make friends in school, he was content to be a delinquent with his brother.

Rui remembered how boring school life was without Ataru around. No matter how strong he was, he still lacked the drive to get into skirmishes. Whenever he and Ataru are placed in different classes, Rui just wouldn’t bother. Life is more interesting when he sees it beside Ataru and he loved interesting things more than he loved studying. It wasn’t like Rui hated studying, in fact he was pretty good at it and he had resort to helping Ataru study whenever it was needed, but it was just so boring to go to school and have good grades and fade into background.

Until now.

He remembered how pissed he got when Ataru came home with a suspension letter. He was away from Ataru’s side for a few _hours_ and something so great happened that it gave a full-on one week suspension? He remembered being pissed at Imai, who was just as pissed that he missed the chance of seeing Ozaki getting his ass kicked.

But it was during the week that Ataru was suspended that Shiota-sensei came to class.

He always had a smile that was neither warm nor menacing. It was… calm. Like he was restraining something within him that he couldn’t show to class. It was when he apprehend Miura that Rui was utterly and completely captivated by the way Shiota-sensei moved. It was like watching an action movie where the assassin moved completely without a sound and damn he thought it was interesting.

For the first time since forever, Rui thought that something interesting happened without Ataru around.

The day he told Irie to come see him after class, Rui followed Irie into the staff room. Shiota-sensei had the same calm— _deadly_ —smile on his face as he signaled Irie to follow him to the back of the gym.

Rui tried his best to stalk them without getting caught, and positioned himself on a bush by the gym’s exit. He saw Irie and Sensei talk.

“Here you go,” Shiota-sensei handed over a real knife to Irie while he took out a plastic green knife. “If you manage to hit me with that knife once, you win and you are free to kill me however you like, but if I can hit you with this plastic one thrice then I’ll win.” Irie laughed (the crazy fucker) and licked his lips.

Irie charged with no hesitation, and Shiota-sensei sidestepped him so easily and hit Irie’s neck with his plastic knife once. “This is the carotid artery, if I’m the one with real knife, you’d be dead now.” A smile and a chiding, Irie growled and tried to charge him once more. Again, Shiota-sensei stepped backwards. When Irie was about to   charge again, Sensei ducked his head and tugged Irie’s clothes until he lost balance and hit him once on his left chest. “The heart. You’re dead twice now.” Irie screamed and kicked the teach’s shin until Sensei fell, but when he was about to drive his knife to Sensei’s heart, nimble hands clapped right in front of Irie’s face and the other dropped his knife immediately.

“A-ah? Huh?”

Shiota-sensei took the knife and point it to Irie’s chin. “Third strike. I guess this means I win then.” His smile was so genuine. He pocketed the real knife with practiced speed and help Irie off the ground. “Don’t be so straightforward with your charges, it makes you easy to read.”

“Let’s do this again!!” Irie lashed, but his face was full of admiration. Shiota-sensei smiled and hand him the plastic knife. “If you hand your homework tomorrow, I’d teach you again. Same goes with you, Banjou-kun.” Shiota-sensei had his eyes on the bush where he hid and nowhere else. “When stalking your prey, learn to still yourself. I can hear you if you move around.”

Rui stood up from his hiding spot, completely in awe. Holy fucking shit. He’d do ten thousand homework if he could be taught to move like motherfucking ninja.

Shiota-sensei was about to leave them before he turned to Rui, a curious smile on his face. “Oh, yeah, do you know where I can find your brother?”

Needless to say, Rui felt like this would be the only interesting thing that he brought for Ataru for a change.


	6. Imai Raichi

**Summary for the Chapter:**

> Seat Number 6 Imai Raichi developed a crush at Shiota-sensei's friend.

It was no secret that Imai Raichi could not read for shit.

It’s just that there wasn’t ever a need to read. He used to be able to terrorize people into reading for him (hey, why do you think people become a delinquent?), but nowadays nobody in Class 5 is afraid of him. Adachi was his bro and Arata is downright annoying to deal with (unless he hold blackmails on Miura or Sakurakouji, _then_ Arata would be his best ally). Arisugawa pretended nobody existed other than Ozaki while Imamura is a natural airhead that seems to pass his tests without knowing what exactly he was doing.

Classical Literature is the thorn of his existence and Raichi, for the love of god, needed to pass this test. Rumor’s been flying around that the shorty teach is crazy good with knives and apparently he is perfectly capable of throwing a javelin thrice his size down to someone’s throat. Banjou brothers are seen with bruises on their throats after a ‘private lesson’ from the teach and the blue-haired guy had told them with a kind goody goody smile that _those who don’t pass this test will have a mandatory supplementary lessons_. And Raichi may be an idiot but he wasn’t a _moron_. The Banjous are one of the good fighters of this class and bruises after private lessons are another thing entirely.

He crammed, like crazy, even had Adachi, Arata, Imamura, and Kusunoki to help him study. But alas, crammings are never the best solution.

The private lessons are held in the back of the gym, and Raichi snuck out before the teach could spot him. He was about to leave the school when he bumped into a beautiful lady with long orange-brown hair who looked expressionless despite carrying a cello case twice her size.

“Hello,” she greeted, her voice quiet and polite. “I am looking for Shiota Nagisa, do you know where I can find him?” Raichi rolled his eyes. “I don’t know, maybe in the back of the gym or something.” Teal-colored eyes scanned him coldly. “Can you take me to him?” Her voice sounded chilly, it left no room for nonsense and it was nothing Raichi ever heard before. His father was a slob (who loved him very much, but still a slob) who never cared too much to talk properly. She has a way of speaking that intimidated him.

“S-sure.” His mouth ran for him and before long he was walking to the very place he’d been running away from. The lady fell a step behind him, her footsteps eerily quiet but she always made her presence known somehow. Raichi found it eerie, but he said nothing.

When they reached the back of the gym, the shorty was pummeling Banjou the older into the ground. “One more time, Ataru-kun, this time plant your feet firmly.” The beautiful lady didn’t bat an eyelash as she walked over from Raichi’s behind to the teacher’s side. “Nagisa,” she called once, and the teacher noticed her immediately. “Oh, Hayami-san you came in perfect timing!” Shiota smiled. “Would you help me teach these children PE while I tutor Imai-kun over here? We shouldn’t be long.”

There was a cold and hardy look on the lady’s face before she nodded. “Anything for a friend, Nagisa. Come now, you three, try and attack me.” She let down her cello case, and readied her stance. “Basic PE is enough, yes?” She asked the shorty while she was avoiding the Banjous’ signature punch. Blue eyes met teal and he smiled. “Of course. Oh, and teach them how to play Hide and Seek and Hunt too! That should be a fun exercise.” The lady was smiling a very slight smile now.

Sensei left the area, beckoning Raichi to come and follow him. But he stayed. He stayed to watch the beautiful lady asked them to hide wherever as long as it was in the courtyard while she went over to a tree and climbed it with only her feet.

Raichi watched, his eyes almost bulging out of his eye-sockets, as she took out a sniper rifle out of her cello case. It looked plastic, but dangerous and menacing nonetheless. “These are paint balls, they won’t hurt you at all.” And with those words, the Banjous, along with Irie, are gone.

The next 10 minutes were the best in Raichi’s life. The beautiful lady stayed in her position by the tree as she spotted Banjou the older first and shot him straight on his head. The paint splattered messily on Banjou’s face. There was a sound of rustling on the bush near Banjou and the beautiful lady sniped there with no hesitation. And then comes the sound of Irie, who growled.

The last one is Banjou the younger, the smart sibling. But it didn’t take long for the beautiful lady to find him either.

“All of you have potentials.” She praised briefly. “But you are lacking some moves. Keep trying to keep up with Nagisa, he is the best we had before.” And then her gaze went to Raichi and Raichi alone. “Would you come along next time too? I would like to repay your kindness.”

Imai Raichi couldn’t read for shit, before he sure can read the meaning behind that tiny little smile on that lady’s face.

The short—Shiota-sensei could _not_ be a normal person to have a very talented sniper as a friend.

* * *

 

The very next day Imai the Blabbermouth spread rumors about how Shiota Nagisa used to work for the secret services as an assassin before being sent here to enjoy his youth.


End file.
